Forget about all other changes, and all other arguments and reasons made, this has been the goal from the start. All those replays, all that feedback, all those discussions aren't going to change this. There is absolutely nothing that is going to change this opinion/reality/choice/wtf.
I'm willing to bet at this point that if Elefants and JTs damage isn't dropped to 280 from 320, the answer will to give Jacksons 660 health. Probably in spite of any debate, input, or questions.
Everything you describe as to what a Jackson 'needs' to be can be accomplished through increasing its close range penetration so that it can reliably penetrate heavy tanks and giving it the 560 health shared by the M10. It can then close, it can deal damage.
Reducing its max range accuracy could be an option too, but not its penetration necessarily.
Increasing the Jackson's health to 560, not 600, means that the vehicle has durability from everything that isn't an Elefant. It's probably not going to get through, but I'd hope you can understand that the StuG and especially Elefant are effective crutches for Ostheer at this point. Try to think of them not as 'killing Jacksons in 2 shots' as they are 'reducing the amount of shots to kill enemy tanks by one'. Have you ever considered that Elefants being so common is a symptom of a greater issue with Ostheer? (That perhaps any amount of changes to the Jackson won't solve?)
In team games, there are rarely more than one or two panthers fielded at any given time. Anything more or less is cost-prohibitive and inefficient. There are, however, often two to three Jacksons per USF player in my experiences. And I'm not even mentioning pop cap.
But the most important question to me is: "Where is the Sherman's role supposed to fit into this equation with this idea of the Jackson?"
+1 to this. Its a perfect summary.
IF (and that is a big if) the Jackson wants to keep its buff to 600+ HP, it has to give in something in return.
All the other TDs that have 640 are seriously vulnerable in one or multiple ways, i.e. being able to be flanked, too slow, too low in range, too little armor.
The Jackson currently is on the only one with 60 range, 200/200+ damage, high moving accuracy, being turreted and fairly immunune to flanking, is fine in live as it is as a glass cannon.
If you want to give it survivability i.e. more hitpoints, something gotta give. Its either range and mobility or more hp and retaining mobility.
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